Reply To: 1957 Evinrude Big Twin 35 Skeg interferes with gears.

[Mumbles]

It sounds like the driveshaft is a tad too long. Measure the distance from the O ring groove to the top of the shaft and if one is longer than the other, it can be ground down. You might want to measure the overall lengths of both shafts first and if the grooves are the same distance from the top, the bottom of the long one can be ground.

You also might want to check that there is nothing in the splined area in the bottom of the crankshaft which is preventing the driveshaft from going in all the way. An old O ring or parts of one in there can do this.